Chrysanthemum plant named ‘Ossa’

ABSTRACT

A chrysanthemum plant named ‘OSSA’ characterized by its medium sized blooms with white ray florets and prolific branching; natural season flower date 1-4 September; blooming for a period of 7 weeks.

BACKGROUND OF THE INVENTION

Ossa is a product of a breeding and selection program for outdoor pot mums (garden mums) which had the objective of creating new chrysanthemum cultivars with a decorative type flower, a natural season flower date around 1-4 September; blooming for a period of 7 weeks. The new plant of the present invention comprises a new and distinct cultivar of Chrysanthemum plant ‘OSSA’ is a seedling resulting from the open pollination among groups of chrysanthemum cultivars maintained under the control of the inventor for breeding purposes. The new and distinct cultivar was discovered and selected as one flowering plant by Rob Noodelijk on a cultivated field in Rijsenhout Holland in September 1996. The plant has been asexually reproduced by cuttings in greenhouses at Rijsenhout Holland. The new cultivar has been found to retain its distinctive characteristics through successive propagations.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention of a new and distinct variety of chrysanthemum is shown in the accompanying drawings, the color being as nearly true as possible with color photographs of this type.

FIG. 1 shows a plant of the cultivar in full bloom.

FIG. 2 shows the various stages of bloom of the new cultivar; and

FIG. 3 shows the various stages of foliage and petiole of the new cultivar.

DESCRIPTION OF THE INVENTION

This new variety of chrysanthemum is of the botanical classification dendranthema grandiflora. The observations and measurements were gathered from plants grown out door in Rijsenhout, Holland under natural day length and temperature and planted week 22 in 1997 and 1998. The natural blooming date of this crop was 1-4 September (week 35). The plants were observed (directly) during the flowering of this crop. The average height of the plants was 32-36 cms. No growth retardants were used. No tests were done on cold or drought tolerance. This new variety produces medium sized blooms with white ray florets and prolific branching.

From the cultivars known to inventor the most similar existing cultivar in comparison to ‘OSSA’ is ‘LINDA’ (U.S. Plant Pat. No. 8,294). When ‘LINDA’ and ‘OSSA’ are being compared the following differences are noticed: The differences of ‘LINDA’ and ‘OSSA’ are (1) Flower size. ‘OSSA’ has bigger flowers. (2) Natural flowering date. ‘OSSA’ flowers much earlier (3) Vigor. ‘OSSA’ has a more vigorous growth.

The following is a description of the 13-week plant and characteristics that distinguish ‘OSSA’ as a new and distinct variety.

The color designations are taken from the plant itself. Accordingly, any discrepancies between the color designations and the colors depicted in the photographs are due to photographic tolerances. The color chart used in this description is: The Royal Horticultural Society Colour Chart, edition 1995.

Botanical Classification Cultivar ‘OSSA’

Bud:

Size.—Medium, cross-section 1.2 cm height 1.0 cm.

Outside color.—Yellow-white 158D.

Involucral bracts.—2 rows, length 7 mm, width 3 mm.

Involucral bracts among disc-florets.—Not present.

Involucral bracts color.—Green 138A.

Bloom:

Type.—Decorative.

Height.—High.

Size.—Medium.

Fully expanded.—5.5-6.0 cm.

Number of blooms per branch.—Approx. 6-7 blooms per branch.

Performance on the plant.—7 weeks.

Seeds.—Not produced.

Fragrance.—Typical chrysanthemum.

Color:

Center of flower.—Immature yellow-white 158 D and greyed-yellow 160 B in the center. Mature white 155 B.

Color of the upper surface of the ray-florets.—White 155 D.

Color of the lower surface of the ray-florets.—White 155 D.

Tonality from distance.—A mounded decorative garden mum with white blooms.

Discoloration to color.—None.

Ray florets:

Texture.—Upper side and under side smooth.

Number.—190-220.

Cross-section.—Concave.

Longitudinal axis of the majority.—Incurved, outer rows straight.

Length of corolla tube.—Short.

Ray-floret margin.—Entire.

Ray-floret length.—2.4-2.8 cm.

Ray-floret width.—0.4-0.6 cm.

Ratio length/width.—High.

Shape of tip.—Rounded.

Disc florets.—None.

Receptacle shape.—Domed raised.

Reproductive organs:

Stamen.—Not present.

Pollen.—Not present.

Styles.—Thin.

Style color.—Yellow-green 144 B.

Style length.—3 mm.

Stigmas.—Yellow-green 144 B.

Stigma width.—1 mm.

Ovaries.—Enclosed in calyx.

Plant:

Type.—A garden mum (pot mum) meant for outdoor use.

Growth habit.—Spreading.

Growth rate.—Rapid.

Height (from soil level).—32-36 cm.

Width.—33-36 cm.

Stem color.—Green 138 A.

Stem strength.—Strong.

Stem brittleness.—Present.

Stem anthocyanin coloration.—Absent.

Length of lateral branch.—From top to bottom 14-15 cm.

Lateral branch color.—Green 138 A.

Lateral branch, attachment.—Weak.

Branching (average number of lateral branches).—Prolific with 7-9 breaks after pinching.

Peduncle length.—3.0-4.0 cm.

Peduncle color.—Green 138 A.

Natural season blooming date.—1-4 September.

Foliage:

Color.—Upper side green 137 A. Under side green 137 D.

Size.—Small, length 5.5 cm width 4.5 cm.

Quantity (number per lateral branch).—12-15.

Shape.—Ovate sometimes round.

Texture upper side.—Glabrous.

Texture under side.—Pubescent.

Venation arrangement.—Palmate.

Shape of the margin.—Serrated.

Shape of base of sinus between lateral lobes.—Pointed.

Margin of sinus between lateral lobes.—Diverging.

Shape of base.—Attenuate.

Apex.—Mucronate.

Differences with the comparison varieties ‘OSSA’ ‘LINDA’ Flowersize 5.5-6.0 cm 4.5-5.0 cm Natural flowering date September 1-4 September 28 Vigor/growth rate Rapid Moderate 

I claim:
 1. A new and distinct variety of chrysanthemum plant as described and illustrated. 